Caped crusading sysadmin rumbles 419er

Dublin cybercafe mayhem

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We've just been forwarded a link to a posting on www.linux.ie telling the tremendous tale of a peripatetic Dublin sysadmin who was instrumental in trapping a Nigerian 419er in one of that fair city's Internet cafes.

As you might expect given the source, Steffen Higel's account is jam-packed with technical detail of how he rumbled the advance fee fraudster, but eventually builds to a nail-biting climax as the police net closes on the sobbing master criminal.

There's a few interesting issues raised along the way, too. Look out for Steffen's obervations about IP addresses the cafe assigns to punters' own laptops. Food for thought.

I work for a busy Dublin Internet cafe, doing some sysadmining and general computer maintenance. On Sunday the 28th of March, I got a rather distressing email from a sysadmin in a large U.S. University. Spamcop had blacklisted our server's external IP address. Abuse mail for the server in question gets sent to my college account (bad practice, I know, but it's a part time job). My college uses Spamcop as a blacklist source. You can probably tell what happened...

Anyway, said email included the full headers of an email which was natted by our server pretending to be from the widow of Mr. Jonas Savimbi, offering the recipient a share of an unspecified large sum of money. The usual panicked thoughts kick in... "Have I fiddled with something which has left us as an open relay?", "Has our server been cracked?", "Have I been sleep-spamming again?". A more reasoned examination of the headers showed that the mail had originated from one of the IP addresses that we assign dynamically to people who bring laptops into the cafe. This is something of a nightmare for cafe operators, we can hardly block outbound smtp but then again it isn't possible for us to manually check every single mail either. Maybe rate limiting is a valid technical solution. Or a contraption which hits the user on the head for every mail they send. So if they send 1 an hour, it's a mild nuisance. But if they send 100 a minute, it'll probably kill them.

I asked around, and a man, described as being black (or is the word African-American these days?), roughly 30, with an accent which seemed half London and half African had been in the cafe with a laptop and had a number of visitors call into his booth and had been there at the given time.

I hate spam more than I hate crackers. I hate spam more than I hate virus writers. I wanted to catch this guy in the act and I wanted to see him hauled off in a paddywagon. We contacted the police, who unfortunately didn't seem willing to do anything about it unless we caught someone in the act of doing something illegal. The daily staff in the cafe were instructed to let me know if said individual turned up again, though honestly, who could be that stupid? My hopes weren't high.

Evidently, a 419er is that stupid. The very next Friday (2nd of April 2004) he turned up again. I was on the bus at the time, just about to go in for another day of world altering research. I ran down as fast as I could and was told that he was on the second floor and hadn't plugged in yet because he wanted one particular booth which is somewhat secluded and was willing to wait.

I sat myself down at a computer in another room, started tailing the daemon.log and waited for the telltale entries. I took a quick flick through the tcpdump manpage, just to make sure I didn't screw up. 20 minutes later, it started to happen. He plugged in, and his Windows XP laptop started to blabber away. WindowsUpdate, Netbios, passport logins. Nothing much happened for a while. The odd DNS request here, the occasional search:

GET /search.php?Keywords=male%20erection&p (I'm not messing!)

on 64.21.81.131, which seems to belong to some direct marketing whorehouse.

He logged into this as well: 66.180.174.12, which seems to be some sort of mail harvesting database. The login is done over SSL, so I can't find out more. If any militant anti-spam vigilantes want to get a good look at how these people organize themselves, that's probably a good place to start.

Then, he spent a bit of time on http://www.emailspidereasy.com. Don't you just love the fake google-textads? He logged into mail.com next, using the email address kendoda at accountant.com. Whatever hash they use for passwords was aaka7zxkcNo. Then, he logged into his yahoo mail account. This was probably to check the account that in which he receives those mails. It looks like the rest happened over SSL.

Then it started. The screen started showing an awful lot of smtp traffic heading out onto the net. I knew that I had to let it go, even if it meant another 48 hours of being blacklisted. If it meant he could be convicted of committing a crime, then I figured it was worth the price. I hope those who received the mail also feel that way. (sorry :-/)

Before I phoned my contact in the Gardai, I had to make sure that he was actually sending out his vile wares. I scped the partial dumpfile onto my laptop, and opened it up in ethereal. Guess what?

[I've noticed that some characters are missing. This seems to be due to our server not being able to keep up]

And on it went. To lots of people. 1178 of them. By that time, two Gardai had called in and wanted to wait until he had sent as many as he was going to. They seemed fairly convinced at that point that our friend was engaged in something less than honest. These weren't computer specialists, but they walked up, knocked on the window of the booth and introduced themselves.

He asks them what the problem is and is told to step away from the computer. He doesn't seem too happy about this, but does so. He's asked his name and is told that he might like to come down for a chat in the local station. He says his wallet and ID are in the booth, so he walks in, rips a USB memory stick from the side of his laptop, tries to swallow it and makes a run for it. Detective number 1 grabs and tries to uff him, detective 2 starts to do the same. A struggle ensues and goes on for a full 10 minutes, basically trying to pin him on the floor and then getting his arms behind so he can be handcuffed. Michelle agrees to co-operate on numerous occasions and each time tries to run to the booth to destroy whatever is on that machine.

Eventually, 2 more gardai arrive and he's cuffed and brought out, crying like a little girl claiming police brutality (which is untrue, they would probably never have even formally arrested him if he hadn't attempted to run). Detective 1 was explaining to me how it's extremely difficult to restrain someone without hurting them. They could have had him subdued in about 10 seconds flat, but there have been instances in the past where a few gardai in this country have caused quite a bit of controversy with their liberal application of force. So this eyewitness applauds the superb work done by these gardai in a very difficult situation. 10 minutes of struggling with someone is pretty tough work.

So he's carted off in a car back to the local station., where he'll get a cozy cell. Myself and detective 1 take a look at the equipment he had... A "mentor" network card (based on the cameo chipset), a badly chewed (but fairly undamaged looking) USB memory stick and a bulky laptop running Windows XP. Open on the screen is MS Word with the exact text of our beloved email and some bulk email program (the icon had a yellow background with a black @ symbol). His phone is ringing in his coat constantly. One of his many guests from his previous visit must want to talk to him.

At one point, 3 guys who would appear to be of similar ethnic background want to come into the room where Michelle was working. They are told we are closed due to a technical problem. They were friendly and understood the situation and departed quickly enough.

Some guys from the computer crime unit turn up, 3 of them. We have a good chat about what evidence I have on the guy. We look through my tcp trace, they same happy enough with what's there. They ask if I managed to sniff any other traffic, http and so forth. They're really hoping that they can get his email password, so with appropriate judicial permission (I assume) they can take a look at who has been mailing him. Yahoo are apparantly extremely uncooperative in this area. He seemed to be using a mail.com address as well. Proof that he is intending on scamming people out of money is what the gardai need. I'm not sure if it's illegal to pretend to be someone you aren't and offer a stranger money that you don't have. I'm guessing that with the tcpdump I gave them, their technicians will be able to get something out of it. I'm more interested in the contents of that USB stick.

So anyway, that's my tale. Michelle has been charged with assault (he tore off detective 1's wrist watch) and is claiming that he can't speak any English. Given the potential scale of the scamming operation, detective 1 reckoned that they'd probably end up handing the evidence over to interpol or whoever works in Quantico (that's the FBI, right?).

What have I learned? Firstly, digging up evidence on criminals is an exciting activity. Secondly, if you're an absentee sysadmin for an Internet cafe, transperantly proxy as much traffic as you can. The logs will prove useful if you are trying to track an abuser's traffic 24 hours after they have left. I was lucky in this respect, I was proxying smtp and http to postfix and squid. The added headers in the mails makes things easier to track. Thirdly, there doesn't seem to be sufficient clarity among those employed in law enforcement concerning the legalities of spam. Hell, I don't know what the laws regarding this sort of thing are. I just know it sucks. Finally, it's a bit out there, but the gardai should forge closer links with the research community Among us, we have a whole lot of knowledge of just about every issue under the sun. We're mostly idealists, and those ideals include a spam-free Internet. And heck, we're cheap!

Hope that provided some amusement. Forward it on to anyone who is interested. Really. I want to see it on the front page of slashdot and el reg within a week. And yes it really happened.

Well, you made it onto El Reg, and deservedly so, we reckon. Good show, sir. ®